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高温超导永磁磁盘和磁环在磁选中的应用前景

现代矿业 1999年第16期24卷 4-7页

作者： j.h.p.沃森许孙曲南安普敦大学物理和天文学系

磁力分选在矿物加工工业中被广泛地用于富集和回收有价矿物。在65-77K的液氮中使用的高Tc超导永磁磁盘和磁环能够产生比传统永磁体强得多的磁力。用磁场B来表示,则决定磁力的重要因素是B^2的梯度,由超导磁盘可获得高达60T^2·cm^(-1)的... 详细信息

磁力分选在矿物加工工业中被广泛地用于富集和回收有价矿物。在65-77K的液氮中使用的高Tc超导永磁磁盘和磁环能够产生比传统永磁体强得多的磁力。用磁场B来表示,则决定磁力的重要因素是B^2的梯度,由超导磁盘可获得高达60T^2·cm^(-1)的值,而从传统永磁体可获得的值约为1-3T_2cm^(-1)。传统永磁体一直被用于筒式磁选机提供磁场和磁场梯度,其磁力使可磁化矿物颗粒抵抗重力而保留在转筒表面,从而与较不易磁化的颗粒实现空间分离;在"开梯度"磁选机中,颗粒靠磁力产生偏转,与下落中的混合粒流分开,即所谓的"落幕"技术。此外,利用在永磁转轮上移动的传送带来导引颗粒也可实现分离。上述各项技术中采用超导永磁体都将更为有利。在以往对完全磁化磁盘的研究中发现,在实现分离过程的高选择性方面存在着一些问题。本文将要讨论,使用部分磁化的磁盘和磁环可大大减少获取高选择性方面的难题。目前超导永磁休尚未满足工业上所要求的可靠性。本文所提出的解决方案是使用与磁通泵相连接的磁通管,以提供廉价的和可靠的超导永磁体源。

关键词：磁选

涡流磁选──一种高回收率、高处理速度、高选择性的工艺

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国外金属矿山 1995年第12期20卷 55-56页

作者：刘维平 j.h.p.沃森李正南英国南安普敦大学低温学学院

我们感谢斯沃博达（Svoboda）博士在信中提出的涡流磁选问题，也感谢《矿物工程》杂志为我们提供了回答斯沃博达博士提出的问题的机会。采用单金属丝及低温实验技术，沃森（Watson）和李（Li）’‘’指出在磁选过程中当物料在金属丝逆... 详细信息

我们感谢斯沃博达（Svoboda）博士在信中提出的涡流磁选问题，也感谢《矿物工程》杂志为我们提供了回答斯沃博达博士提出的问题的机会。采用单金属丝及低温实验技术，沃森（Watson）和李（Li）’‘’指出在磁选过程中当物料在金属丝逆流侧（作用磁场和流向相互平行并和金属丝轴向垂直）被捕收时，限制选择性的因素之一是机械夹带作用。这是一种十分弱的磁性或非磁性颗粒和磁性沉积物碰撞并留在沉积物中的过程。通常选择合适长度（通常较短）的分选箱，可以减弱机械夹带作用”·’j。但是，对于各种实际情况，通过涡流磁选，磁性物料在金属丝顺流例被捕收，机械夹带过程可被消除。对于圆形断面的单金属丝而言，当雷诺数Re大于6而小于40时，会产生这种现象，此时．涡流变得不稳定［‘1。后续的金属丝在顺流处增加了涡流结构的稳定区域。在涡流磁选中，颗粒首先被吸引到金属丝的逆流侧，但是．在使用条件下（流量、流速、磁场等），矿粒被冲入到边界层中。如果矿粒的质量中心移动偏离金属丝的距离大干边界层厚度的03倍．那么它们再次进入主流区而不被捕收。如果矿粒停留在边界层03倍以内，那么它们就进入涡流区。在该区域，如果矿粒具有足够强的磁性，则可被捕收。那些磁性不够强...

关键词：选矿涡流磁选回收率处理速度选择性

Z型g-C_(3)N_(4)/WO_(3)•h_(2)O的制备及其光催化CO_(2)还原性能

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精细化工 2024年第4期41卷 858-864,871页

作者：张健翁森石俊杰蔡静宇肖龙强福州大学石油化工学院福建福州350108 清源创新实验室福建泉州362801

以石墨相氮化碳(g-C_(3)N_(4))和二水合钨酸钠为原料,采用水热合成法制备了复合材料g-C_(3)N_(4)/WO_(3)•h_(2)O(CNW-1),通过XRD、XpS、SEM、TEM对其进行了表征,探究了298 K、0.1 Mpa条件下其对CO_(2)的可见光催化还原性能,并提出了可... 详细信息

以石墨相氮化碳(g-C_(3)N_(4))和二水合钨酸钠为原料,采用水热合成法制备了复合材料g-C_(3)N_(4)/WO_(3)•h_(2)O(CNW-1),通过XRD、XpS、SEM、TEM对其进行了表征,探究了298 K、0.1 Mpa条件下其对CO_(2)的可见光催化还原性能,并提出了可能的反应机理。通过调控WO_(3)结晶水含量可以实现CO和Ch4的产率调节,在反应10 h后,CNW-1具有最高的Ch4产率(0.33μmol/g),而g-C_(3)N_(4)/WO_(3)(CNW)具有最高的CO产率(0.67μmol/g)。该研究为CO_(2)选择性还原为C1化合物提供了一种有效策略,同时突出了以g-C_(3)N_(4)作为半导体构建Z型光催化体系在催化领域的应用潜力。

关键词：二氧化碳光催化还原石墨相氮化碳三氧化钨 Z型光催化剂催化技术

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The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical physics 2024年第3期76卷 51-61页

作者： h W A Riaz j Lin Department of physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.huang Z.Yang S.Y.Yang Z.h.Dai Y.j.Liu j.h.Liao G.Y.Zhong Z.j.Xie Y.p.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure heterostructure photothermal effect photocatalyst hydrogen evolution

由超拍电子伏特加速器产生的超高能伽马射线气泡

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Science Bulletin 2024年第4期69卷 449-457页

作者： LhAASO Collaboration Zhen Cao Chuandong Gao Cong Li Ruo-Yu Liu Ruizhi Yang 不详 Key Laboratory of particle Astrophyics&Experimental physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China TIANFU Cosmic Ray Research Center ChengduChina Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China University of Science and Technology of China Hefei 230026China

We report the detection of aγ-ray bubble spanning at least 100deg2 in ultra-high energy(UhE)up to a few peV in the direction of the star-forming region Cygnus X,implying the presence super peVatron(s)accelerating protons to at least 10 peV.A log-parabola form with the photon indexΓ(E)=(2.71±0.02)+(0.11±0.02)×log10(E/10 TeV)is found fitting the gamma-ray energy spectrum of the bubble *** sources,“hot spots”correlated with very massive molecular clouds,and a quasi-spherical amorphousγ-ray emitter with a sharp central brightening are observed in the *** the core of~0.5°,spatially associating with a region containing massive OB association(Cygnus OB2)and a microquasar(Cygnus X-3),as well as previously reported multi-TeV sources,an enhanced concentration of UhEγ-rays is observed with 2 photons at energies above 1 *** general feature of the bubble,the morphology,and the energy spectrum,are reasonably reproduced by the assumption of a particle accelerator in the core,continuously injecting protons into the ambient medium.

关键词： Cosmic rays γ-rays Interstellar medium Star cluster

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu G.G.Wang A.hu Y.Li K.B.Thacker j.p.Weiler h.hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada Global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(SY)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,Chemical Sludge(CSF),physical Sludge(pSF)and Comprehensive Sludge Factors(and CpSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** CpSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the pSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition process parameter

Observability Analysis of Integrated Electricity and heating Systems with Thermal Quasi-dynamics in pipelines

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CSEE journal of power and Energy Systems 2024年第3期10卷 1145-1158页

作者： Zhigang Li Wenjian Zheng junbo Zhao j.h.Zheng Q.h.Wu School of Electric power Engineering South China University of TechnologyGuangzhou 510641China Fuzhou Changle District power Supply Company of State Grid Fujian Electric power Co. Ltd.Fuzhou 350000China Department of Electrical and Computer Engineering University of ConnecticutStorrsCT 06269USA CSEE IEEE

Observability analysis(OA)is vital to obtaining the available input measurements of state estimation(SE)in an integrated electricity and heating system(IEhS).Considering the thermal quasi-dynamics in pipelines,the measurement equations in heating systems are dependent on the estimated results,leading to an interdependency between OA and *** OA methods require measurement equations be known exactly before SE is performed,and they are not applicable to *** bridge this gap,a scenario-based OA scheme for IEhSs is devised that yields reliable analysis results for a predefined set of time-delay scenarios to cope with this *** its core procedure,the observable state identification and observability restoration are formulated in terms of integer linear *** tests are conducted to demonstrate the validity and superiority of the proposed formulation.

关键词： Integrated electricity and heating system measurement observability analysis state estimation thermal quasi-dynamics

通过深度学习预测脑膜瘤的等级和病理标志物表达

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国际医学放射学杂志 2024年第4期 496-497页

作者： j.W.Chen Y.p.Xue L.h.Ren K.Lv p.Du h.X.Cheng 胡佳圆

摘要目的建立一个深度学习（DL）模型用于预测脑膜瘤的肿瘤等级和病理标志物的表达。方法回顾性纳入2018年9月—2021年12月在2家医院接受手术切除的1 192例

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